This invention relates to a process for applying a releasible protective layer to an adhesive surface of a flexible sheet flooring product. The protective layer covers and protects the adhesive surface of the flooring product prior to installation, and facilitates handling of the flooring product during transport and installation. The invention allows the flooring product to be conveniently rolled up or folded without wrinkling or creasing the protective layer. Wrinkles and creases in the protective layer generally transfer to the wear layer causing aesthetic deformations and damage to the flooring product.
A laminated sheet vinyl flooring product, such as described in Applicant's co-pending U.S. patent application Ser. No. 08/853,677 filed on May 9, 1997, is shown in FIG. 1. The complete disclosure of this application is incorporated herein by reference. The flooring product shown includes a resilient vinyl wear layer, a felt fiber layer overlying the wear layer, a pressure-sensitive adhesive coating applied to the fiber layer, and a plastic release liner covering the adhesive coating.
After manufacture, the flooring product is typically rolled up to facilitate storage, transport, and installation. In order to roll up the flooring product without damaging its wear layer, the product must be sufficiently thin and flexible to accommodate slight changes in its linear dimension between the top surface and the bottom surface. This problem is explained further with reference to FIG. 2. As shown, a standard laminated felt-backed flooring product is typically rolled up with the wear layer facing out. Due to the thickness of the flooring product and because the wear layer does not generally stretch, the felt backing becomes compressed when rolled.
In the laminated flooring product shown in FIG. 1, rolling in this manner will likewise cause the felt layer and release liner to compress. Thus, if the release liner is first mated with the adhesive-coated felt backing when the flooring product is laid flat and the flooring product is subsequently rolled up, the release liner will compress and wrinkle. These wrinkles create permanent deformations in the wear layer, and generally result in a flooring product which is unacceptable to the end user.
The present invention addresses this problem by applying the release liner to the flooring product after the flooring product is already curved in a roll. When the flooring product is later unrolled, it lies flat without any wrinkles in the release liner and without damage to the wear layer. Moreover, application of the invention is not limited to the laminated sheet flooring product shown in FIG. 1.